Acisoma variegatum Kirby, 1898

Mens, Lotte P., Schütte, Kai, Stokvis, Frank R. & Dijkstra, Klaas-Douwe B., 2016, Six, not two, species of Acisoma pintail dragonfly (Odonata: Libellulidae), Zootaxa 4109 (2), pp. 153-172 : 159

publication ID	https://doi.org/ 10.11646/zootaxa.4109.2.3
publication LSID	lsid:zoobank.org:pub:3DF4E74C-F422-48AD-AFEE-F3B0FEA8F443
DOI	https://doi.org/10.5281/zenodo.5672999
persistent identifier	https://treatment.plazi.org/id/244B882F-2328-762A-FF71-2194FD6AA4B9
treatment provided by	Plazi
scientific name	Acisoma variegatum Kirby, 1898
status

Treatment

Acisoma variegatum Kirby, 1898 View in CoL —Slender Pintail

( Figs. 4 View FIGURE 4 A, 5A–D, 6A, 7A, 8A, 10A)

Material. Tanzania: 8 males, Mpanda, 11-x-1970, J. Kieland ( RMNH); 5 males, Sibweza, 20–23- v-1966/ 26 - ix1966/ 24-vi-1968 / 21-xi-1968, J. Kieland ( RMNH); 1 male, Korogwe, 07-ii-1964, G.M.L. Bergers ( RMNH).—D.R. Congo: 1 male, Katanga, Mutwale, 06-iv-1961, J.J. Symoens ( RMNH); 1 male, Katanga, Mulandi, 11-ii-1963, J.J. Symoens ( RMNH); 1 male, Katanga, Kiubo, 05-ix-2011, K.-.D. B. Dijkstra ( RMNH).— Kenya: 2 males, Amboseli, viii-1980, collector unknown ( RMNH).— Uganda: 1 male, Entebbe, botanical garden, 30-iii-1999, V. Clausnitzer ( RMNH).— South Africa: 2 males, KwaZulu-Natal, Ndumo Game Reserve, Mgagabhuleni, 31-ii-2014, K.-.D.B. Dijkstra ( RMNH); 1 male, KwaZulu-Natal, 7 km ESE of Manguzi, Kosi Bay area, inflow of Nhlange and Amanzimnyama lakes, 02-iv-2014, K.-.D.B. Dijkstra ( RMNH); 1 male, KwaZulu-Natal, 15 km NE of Manguzi, Kosi Bay estuary, 03-iv-2014, K.-.D.B. Dijkstra ( RMNH).

Male diagnosis. Typical of the group lumped formerly under A. panorpoides by the (a) extensively white labrum, labium, thorax and underside of S3–7; (b) low number of Fw Ax, most often 7½ but sometimes 8½; (c) 1 cell in Fw triangle, but 2 cells in 24% of examined wings; (d) long Fw Pt, about 13–16% as long as Hw; (e) abdomen that narrows abruptly on S 5 in lateral view, with S6–10 slender ( Fig. 7 View FIGURE 7. S 2 – 10 A); (f) fragmented and frayed white markings on S2–5 and large white lateral spots on S7 ( Fig. 7 View FIGURE 7. S 2 – 10 A); and (g) broad and triangular lobe of hamule ( Fig. 8 View FIGURE 8 A). Unique within the genus by the (1) most slender abdomen, with the tergite of S5 below the lateral carina almost invisible in lateral view and S6 always more than 2.5x as long as high, and the ventral borders of S5 and S6 confluent ( Fig. 7 View FIGURE 7. S 2 – 10 A); (2) almost always partly white ventral carina of S4, extending to an always white corner with the apical carina; and (3) always largely white and thus never wholly black lateral carina of S5. Overlaps with A. inflatum in eastern and southern Africa with which it shares the (4) sublateral black marking concentrated on the basal side of S4 ( Fig. 7 View FIGURE 7. S 2 – 10 A); and (5) rather wide base of the hook of the hamule ( Fig. 8 View FIGURE 8 A); but differs by the unique characters mentioned as well as its generally (6) larger size, with Hw 21–25 mm.

Range and ecology. More localised than A. inflatum , ranging from Ethiopia to Katanga and northern South Africa ( Fig. 9 View FIGURE 9 B). Although the distribution seems to follow the more elevated Afromontane part of the continent, the species appears to favour more open and eutrophic and often low-lying and expansive marsh habitat where it overlaps with A. inflatum , such as flood plains.